Cotter key



Jan. 9, 1951 J. A. M LEAN, JR, ET AL 2,537,841

COTTER KEY Filed Aug. 30, 1945 Patented Jan. 9, 1951 COTTER KEY John A.MacLean, Jr., Winnetka, m., and Benjamin Franklin Money, Tulsa, Okla.

Application August 30, 1945, Serial No. 613,578

1 Claim.

Our present invention relates to cotter keys and particularly to thoseof a type having a plurality of surfaces offset from one another andadapted forcibly to engage the wall of an appropriate cotter-receivingopening, whether of normal or somewhat over-size, thereby to preventratting of the cotter key and the resultant wear of both the cotter keyand the wall of the openlng.

In general, it is an object of our invention to provide a cotter keyhaving leg portions offset from one another in a manner and at aposition such that said portions forcibly engage the wall of a normal oroversize cotter-receiving opening and flex relatively as a result ofresiliency and/or deformation to compensate for the size of the,

opening.

As is usual, the cotter key presently contemplated has two adjacent legsjoined by an integral head loop, but additionally and distinctively hastwo portions of the adjacent legs offset from one another, so that thelegs remain adjacent with their ends in parallel relationship andconnected by angularly disposed and adjacent intermediate portions.

It is another object of this invention to provide an improved cotter keycharacterized by a reversely bent intermediate portion in each of thelegs, such that each of the legs has parallel portions offset sidewisewith one portion remaining aligned with the head loop, While the otherportion is parallel to and offset from such alignment.

Other objects and advantages of our invention will appear from thefollowing detailed description, wherein reference is made to theaccompanying drawings.

Referring to the single sheet of drawings,

Figs. 1, 2, and 3 are, respectively, side, top, and end elevationalviews of a preferred form of our improved cotter key as it appearsbefore being placed in the cotter-receiving opening of a bolt, pin, orother part with which it is adapted to be used; and

Fig. 4 is a top elevational View of a cotter key of the type shown inFig. 1 when installed in the opening of a part which is indicated insection.

Referring to the structure of theexemplary embodiment of our cotter keyshown in Figs. 1 to 4, inclusive, of the drawings, it comprises a pieceof normally half-round metal wire which has been return-bent and formedto define a head loop In with legs I2 and I3 projecting therefrom inadjacent and closely spaced relation. One leg, such as the leg I2 of theillustrated embodiment, is desirably somewhat longer than the other tofacilitate the separation of the legs after the installation of thecotter key. The substantially flat faces of the half-round wire stockface inwardly and lie adjacent one another as well as forming the innersurface of the head loop. The material used in the wire stock isdesirably steel, such as that which has been found suitable for cotterkeys and which possesses some resilience and the capability ofdeformation.

Either before or after, and preferably after, the formation of thecotter key from the halfround wire stock; the legs I2 and I3 aredeformed by reverse bends I2a, I2b, I3a, and I311 so that their oppositeend'portions are offset from one another and parallel. Both legs beingbent in like manner and crosswise of the adjacent flat surfaces thereof,the legs remain in adjacent and juxtaposed relation throughout theirlength. The position of the bends, in addition to being intermediate theends of the legs, is desirably near the head loop and such that when thecotter key is installed in a cotter-receiving opening of a part withwhich it is used, as shown in Fig. 4, both bends of the legs fall withinthe confines of the cotter-receiving opening.

In order to limit the necessary axial length of a cotter-receivingopening which is adapted to coact with the cotter key in the desiredmanner, the bends are preferably close together. To facilitate theinsertion of the cotter key into an appropriate cotter-receiving openingthe angularity of the reverse bends is such that the angularly disposedconnecting portions of the legs between the reverse bends have gradualslopes and curvatures between the end portions of the legs. Because ofthe desired limitation of the separation between the reverse bends andthe gradual slope of the angularly disposed intermediate portions it hasbeen found desirable to limit the offset relationship of the endportions of the legs in most instances to less than half the width ofthe legs. Such a limitation of the offset relationship still leaves awide variation in the sizes of cotter-receiving openings into which thedisclosed cotter key will firmly fit. It also provides a cotter keystructure which is adapted to the necessary deformation for a forced fitin a relatively small cotter-receiving opening.

Since the reverse bends I 2a, IZb, I3a and I3b in the two legs of thecotter key are crosswise, of the fiat surfaces of the adjacent legs,both legs individually seat themselves and engage the Wall of acotter-receiving opening, such as I4, in

key legs with the wall of the cotter-receiving 7 opening at a pluralityof separated positions insures the prevention of rattling of :the'cotter key in the opening and movement of the key that would result inwear. of the cotter key legs in the usual manner serves additionally tohold the. cotter key in its position within the opening:

Althoughthere are various ways in which-a cottenkey of the disclosedtype mightbe made inthe present instance, it is preferred that thedeformation comprising the reverse lateral bends 12a, 12b, 13a, and I3!)shall be accomplished after theformation of the cotter key into itsadiacent legs and the adjoining head loop. One manner ofaccomplinshingthedesired deformation is by bending the legs in a suitable die inapunch' press;

While we have illustrated a preferred embodiment' of ourinvention, manymodifications may be -made without departing from-the spirit of theinvention, and we-do not wish to be limited to the-precise details ofconstruction set forth, but desiretoavail ourselves of all changeswithin the scope ofthe appendedclaim.

Having thusdescribed our invention, what we claim as new anddesire tosecure by Letters Patent of'the United States, is:

A- cotter key adapted forcibly to engage the The spreadingof theendswall of an appropriate cotter-receiving opening at a plurality ofspaced positions and in transverse planes and comprising, incombination, a pair of legs made of half-round wire stock and extendingin adjacent and juxtaposed relationship from an integral head loop withthe fiat sides of the half-round stock facing one another, said headloop having substantially plane side faces and merging with the legs;through smoothly curved portions, the mid-portions of said legs beingbent in the same manner near the head loop in directions paralleling andlateral to. the flat sides of the legs and at like positions so thatsubstantially coplanar surfaces of the legs lie adjacent one anotheralong the full length of one of the legs, the end portions of the legson opposite sides of the bends being substantially parallel and inofiset relationship to one another, the end portions of the legs remotefrom the head loop being offset from the planes of the head loop sidefaces, so that when driven into a cotter-receiving opening the offsetportions bind on sides of the opening in directions lateral to thoseengaged by said curved portions.

JOHN A. MACLEAN. JR. BENJAMIN FRANKLIN MONEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Num er Name Date 894,041 Norris July 21, 19081,244,076 Pfister Oct. 23, 1917 1,308,018 Wil on June 24, 1919 1,849,605Whitlock Mar. 15, 1932 1,898,071 Wildin Feb. 21, 1933, 2,098,185Hannaford Nov.- 2, 1937 2,266,689 Lemison Dec. 16, 1941 2,372,884 DavisApr. 3, 1945

